progress doesn't compel to us settle century long debate about the role of government for all times. but it does require us to act in our time. >>reporter: some of the key themes from the president speech today on the capitol steps. now the day began with public ceremony on the steps of the capitol before a crowd that may have surpassed 1 million people. david muir watched date of history unfold. >> white house salute to the president. about to be sworn in before the nation. first at one point 7 mile trip to the capitol. ahead of the president on the west front of the capitol, former president. secretary of state. cheers of national maul for the clinton. mrs. clinton lacking better after the fall. before the father arrived, the president growing girls. sasha and malia 11 and 14 wearing j crew and growing up before a nation. then their mother. first lady michelle obama. >> mrs. michelle obama. >>reporter: to thunder applause ushering in new term and the new bangs first lady tweeting blessed to be joining so many of my fellow americans gather to watch the inauguration. ♪ and then the